xref: /freebsd/contrib/llvm-project/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
1 //===- DlltoolDriver.cpp - dlltool.exe-compatible driver ------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Defines an interface to a dlltool.exe-compatible driver.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/ToolDrivers/llvm-dlltool/DlltoolDriver.h"
14 #include "llvm/ADT/Optional.h"
15 #include "llvm/ADT/StringSwitch.h"
16 #include "llvm/Object/COFF.h"
17 #include "llvm/Object/COFFImportFile.h"
18 #include "llvm/Object/COFFModuleDefinition.h"
19 #include "llvm/Option/Arg.h"
20 #include "llvm/Option/ArgList.h"
21 #include "llvm/Option/Option.h"
22 #include "llvm/Support/Host.h"
23 #include "llvm/Support/Path.h"
24 
25 #include <vector>
26 
27 using namespace llvm;
28 using namespace llvm::object;
29 using namespace llvm::COFF;
30 
31 namespace {
32 
33 enum {
34   OPT_INVALID = 0,
35 #define OPTION(_1, _2, ID, _4, _5, _6, _7, _8, _9, _10, _11, _12) OPT_##ID,
36 #include "Options.inc"
37 #undef OPTION
38 };
39 
40 #define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
41 #include "Options.inc"
42 #undef PREFIX
43 
44 static const llvm::opt::OptTable::Info InfoTable[] = {
45 #define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X7, X8, X9, X10, X11, X12)      \
46   {X1, X2, X10,         X11,         OPT_##ID, llvm::opt::Option::KIND##Class, \
47    X9, X8, OPT_##GROUP, OPT_##ALIAS, X7,       X12},
48 #include "Options.inc"
49 #undef OPTION
50 };
51 
52 class DllOptTable : public llvm::opt::OptTable {
53 public:
54   DllOptTable() : OptTable(InfoTable, false) {}
55 };
56 
57 // Opens a file. Path has to be resolved already.
58 std::unique_ptr<MemoryBuffer> openFile(const Twine &Path) {
59   ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> MB = MemoryBuffer::getFile(Path);
60 
61   if (std::error_code EC = MB.getError()) {
62     llvm::errs() << "cannot open file " << Path << ": " << EC.message() << "\n";
63     return nullptr;
64   }
65 
66   return std::move(*MB);
67 }
68 
69 MachineTypes getEmulation(StringRef S) {
70   return StringSwitch<MachineTypes>(S)
71       .Case("i386", IMAGE_FILE_MACHINE_I386)
72       .Case("i386:x86-64", IMAGE_FILE_MACHINE_AMD64)
73       .Case("arm", IMAGE_FILE_MACHINE_ARMNT)
74       .Case("arm64", IMAGE_FILE_MACHINE_ARM64)
75       .Default(IMAGE_FILE_MACHINE_UNKNOWN);
76 }
77 
78 MachineTypes getMachine(Triple T) {
79   switch (T.getArch()) {
80   case Triple::x86:
81     return COFF::IMAGE_FILE_MACHINE_I386;
82   case Triple::x86_64:
83     return COFF::IMAGE_FILE_MACHINE_AMD64;
84   case Triple::arm:
85     return COFF::IMAGE_FILE_MACHINE_ARMNT;
86   case Triple::aarch64:
87     return COFF::IMAGE_FILE_MACHINE_ARM64;
88   default:
89     return COFF::IMAGE_FILE_MACHINE_UNKNOWN;
90   }
91 }
92 
93 MachineTypes getDefaultMachine() {
94   return getMachine(Triple(sys::getDefaultTargetTriple()));
95 }
96 
97 Optional<std::string> getPrefix(StringRef Argv0) {
98   StringRef ProgName = llvm::sys::path::stem(Argv0);
99   // x86_64-w64-mingw32-dlltool -> x86_64-w64-mingw32
100   // llvm-dlltool -> None
101   // aarch64-w64-mingw32-llvm-dlltool-10.exe -> aarch64-w64-mingw32
102   ProgName = ProgName.rtrim("0123456789.-");
103   if (!ProgName.consume_back_insensitive("dlltool"))
104     return None;
105   ProgName.consume_back_insensitive("llvm-");
106   ProgName.consume_back_insensitive("-");
107   return ProgName.str();
108 }
109 
110 } // namespace
111 
112 int llvm::dlltoolDriverMain(llvm::ArrayRef<const char *> ArgsArr) {
113   DllOptTable Table;
114   unsigned MissingIndex;
115   unsigned MissingCount;
116   llvm::opt::InputArgList Args =
117       Table.ParseArgs(ArgsArr.slice(1), MissingIndex, MissingCount);
118   if (MissingCount) {
119     llvm::errs() << Args.getArgString(MissingIndex) << ": missing argument\n";
120     return 1;
121   }
122 
123   // Handle when no input or output is specified
124   if (Args.hasArgNoClaim(OPT_INPUT) ||
125       (!Args.hasArgNoClaim(OPT_d) && !Args.hasArgNoClaim(OPT_l))) {
126     Table.printHelp(outs(), "llvm-dlltool [options] file...", "llvm-dlltool",
127                     false);
128     llvm::outs() << "\nTARGETS: i386, i386:x86-64, arm, arm64\n";
129     return 1;
130   }
131 
132   for (auto *Arg : Args.filtered(OPT_UNKNOWN))
133     llvm::errs() << "ignoring unknown argument: " << Arg->getAsString(Args)
134                  << "\n";
135 
136   if (!Args.hasArg(OPT_d)) {
137     llvm::errs() << "no definition file specified\n";
138     return 1;
139   }
140 
141   std::unique_ptr<MemoryBuffer> MB =
142       openFile(Args.getLastArg(OPT_d)->getValue());
143   if (!MB)
144     return 1;
145 
146   if (!MB->getBufferSize()) {
147     llvm::errs() << "definition file empty\n";
148     return 1;
149   }
150 
151   COFF::MachineTypes Machine = getDefaultMachine();
152   if (Optional<std::string> Prefix = getPrefix(ArgsArr[0])) {
153     Triple T(*Prefix);
154     if (T.getArch() != Triple::UnknownArch)
155       Machine = getMachine(T);
156   }
157   if (auto *Arg = Args.getLastArg(OPT_m))
158     Machine = getEmulation(Arg->getValue());
159 
160   if (Machine == IMAGE_FILE_MACHINE_UNKNOWN) {
161     llvm::errs() << "unknown target\n";
162     return 1;
163   }
164 
165   Expected<COFFModuleDefinition> Def =
166       parseCOFFModuleDefinition(*MB, Machine, true);
167 
168   if (!Def) {
169     llvm::errs() << "error parsing definition\n"
170                  << errorToErrorCode(Def.takeError()).message();
171     return 1;
172   }
173 
174   // Do this after the parser because parseCOFFModuleDefinition sets OutputFile.
175   if (auto *Arg = Args.getLastArg(OPT_D))
176     Def->OutputFile = Arg->getValue();
177 
178   if (Def->OutputFile.empty()) {
179     llvm::errs() << "no DLL name specified\n";
180     return 1;
181   }
182 
183   std::string Path = std::string(Args.getLastArgValue(OPT_l));
184 
185   // If ExtName is set (if the "ExtName = Name" syntax was used), overwrite
186   // Name with ExtName and clear ExtName. When only creating an import
187   // library and not linking, the internal name is irrelevant. This avoids
188   // cases where writeImportLibrary tries to transplant decoration from
189   // symbol decoration onto ExtName.
190   for (COFFShortExport& E : Def->Exports) {
191     if (!E.ExtName.empty()) {
192       E.Name = E.ExtName;
193       E.ExtName.clear();
194     }
195   }
196 
197   if (Machine == IMAGE_FILE_MACHINE_I386 && Args.getLastArg(OPT_k)) {
198     for (COFFShortExport& E : Def->Exports) {
199       if (!E.AliasTarget.empty() || (!E.Name.empty() && E.Name[0] == '?'))
200         continue;
201       E.SymbolName = E.Name;
202       // Trim off the trailing decoration. Symbols will always have a
203       // starting prefix here (either _ for cdecl/stdcall, @ for fastcall
204       // or ? for C++ functions). Vectorcall functions won't have any
205       // fixed prefix, but the function base name will still be at least
206       // one char.
207       E.Name = E.Name.substr(0, E.Name.find('@', 1));
208       // By making sure E.SymbolName != E.Name for decorated symbols,
209       // writeImportLibrary writes these symbols with the type
210       // IMPORT_NAME_UNDECORATE.
211     }
212   }
213 
214   if (!Path.empty() &&
215       writeImportLibrary(Def->OutputFile, Path, Def->Exports, Machine, true))
216     return 1;
217   return 0;
218 }
219